


Fate Stay Fairy Tail

by TariSilmarwen



Category: Fairy Tail
Genre: Alternate Universe - Fusion, Angst, Angst and Feels, Canon-Typical Violence, Cross-Posted on FanFiction.Net, Cross-Posted on Tumblr, F/M, Fate/Stay Night AU, Gen, unrelated oneshot collection
Language: English
Status: In-Progress
Published: 2020-01-20
Updated: 2020-02-23
Packaged: 2021-02-27 12:35:54
Rating: Teen And Up Audiences
Warnings: No Archive Warnings Apply
Chapters: 5
Words: 3,594
Publisher: archiveofourown.org
Story URL: https://archiveofourown.org/works/22327198
Author URL: https://archiveofourown.org/users/TariSilmarwen/pseuds/TariSilmarwen
Summary: Ten years after the disastrous Grail War that orphaned him, Gray would be found competing in the contest himself, alongside his sword-wielding Saber-class Servant Erza. This time, he vows to protect everyone.
Relationships: Gray Fullbuster & Ur, Gray Fullbuster/Erza Scarlet, Natsu Dragneel & Gray Fullbuster, Natsu Dragneel & Lucy Heartfilia
Kudos: 9





	1. Prologue

**Author's Note:**

> I can't take full credit for this idea. "Seductive Grayza Anon" over on Tumblr (a friendly user who dropped suggestions and prompts and headcanons in the inboxes of various Grayza shippers to grossly assault them with feels or inspire them to create content) is the one who first suggested "Grazya as Shirou and Saber" and I just kind of slowly descended into that hell from there.
> 
> There's not gonna be much of an actual plot; this is mostly a collection of one-shots set in the same Fate/Stay Night AU, featuring Gray as the main protag with Ezra as his Saber.
> 
> Heavy ship bias towards Grayza.
> 
> Anyway let's dive in! We'll begin right with the tragic protagonist backstory lol.

Gray's world ended in fire and ice.

He clawed his way out of a pile of burning rubble, his lungs coughing harshly, rattling his small frame. No sooner had he begun to stand than he was buffeted by a violent freezing gush of wind and snow.

Gray stumbled to the side, his arms snapping around himself, fingers clinging to the fabric of his light jacket. Teeth chattering, he looked up at the horror before him.

A gaping black hole floated in the sky, dripping liquid fire from the edges. Whatever the mud touched, houses, trees, and even—Gray saw with horror—people burst into orange flame, the dancing tongues leaping high into the night sky.

In the center of the maelstrom was a roaring, rampaging... _creature._ Gray felt his throat tighten with terror at the sight of it. It was huge and towering, misshapen, an abomination of nature. Clawed hands shredded wood and flesh as it swung its great arms, rushing icy wind following in the wake.

Gray's frozen feet staggered back. His eyes darted around frantically, straining through the dark and the snow and his terrified tears.

"Mom!" he called hoarsely, still coughing. "Dad!"

There was no answer. Nothing but screams all around him, rending stone, whistling wind.

Flaming timbers from the roof cracked and collapsed behind him. Gray gasped, lunging forward out of the way, feeling hot sparks pop against his back.

He fled, tripping over rubble and bodies. He didn't know where he was going. He just knew he was surrounded by death and fear and it was suffocating him.

Voices cried out all around him as he ran. People were screaming, wailing, reaching out, begging to be saved.

Gray clasped his hands over his ears, whimpering.

He rand blindly through the hell and chaos, and when his foot caught on a broken piece of masonry he tripped and went careening into the wet mud and snow and didn't bother to rise, waiting for the end to come.

-FT-

Ur wandered through the aftermath in the gray morning, nursing her Grail-poisoned shoulder. A thousand tiny burning shards of ice tingled through her arm. She grit her teeth against the pain, her free hand tightening.

The wound was grievous. She already knew there would be no recovering from it. Even now her fingertips were beginning to turn numb.

But the demon was dead. The Grail had been banished. No more harm could come to this world.

The icy breeze whistled softly in her ears. She looked up, searching the desolate ruin for signs of life.

There was nothing but rubble, and burnt or frozen corpses.

Dejected, she almost turned to begin the long stumbling trek out of town.

A sound from her right froze her steps.

It was a soft whimpering, coming from under a pile of snow-covered debris.

Gasping, Ur lunged forward, dropping heavily to her knees and clawing at the splintered wood and soggy wet dirt clods. Her fingernails scratched and scratched, digging out frantic handfuls until she uncovered him: a boy, half-frozen, hideously pale and shivering, but alive.

_Alive._

"It's okay!" she told the quivering child, enveloping him in her arms at once, tucking his snow-covered head under her chin. "It's okay, I've got you now. You're gonna be okay."

He sniffled against her parka, dark gray eyes glassy and tear-stained.

"They're dead," he warbled softly. "Mom... dad... everyone's dead."

"Not you," Ur pointed out, running a hand through his hair. "And not me." She pulled him back to look at his face, hands on his shoulders, offering him a gentle smile. "So we'd better stick together, right?"

He stared at her uncomprehendingly a long moment.

She tapped his shoulder. "Come on," she said, starting to get up. "On our feet. Let's go see if we can find anyone else."

The boy hesitantly got stiff legs underneath him. His uncertain look was beginning to fade.

When she held out her hand, he took it, and she led him away from the place that was to be his grave, sunlight beginning to break through the clouds and shine warmly upon their heads.


	2. Alter

**Notes for the Chapter:**

> First one is kinda short. And angsty. Because how else was I supposed to take the suggestion "Erza vs Gray. Gate of Fiore vs Unlimited Ice Works." except as a free invitation to throw an evil Erza Alter at Gray for Dramatic Purposes?
> 
> This may or may not get expanded later, should I decide to explore more Heaven's Feel related material.

Gray refused to believe the swordswoman he knew, so strong and radiant, sad and yet driven by noble purposes, could have wound up like this.

The bright red of her hair faded and dull, her armor black as night with bloodshot red piping licking like flames up the sides. Her warm brown eyes a burning, dead, gold. Her faint smile, so often given, gone for good.

The Grail's corruption permeated her, the myriad of weapons bristling from her Noble Phantasm pointed right at him. She sneered as she raised her sword.

"What now, Ice-Mage?" she taunted. "Will you keep to your foolish ideals and slay the woman you hold such affection for, to save this pitiful, undeserving world?"

Gray's mouth ground tighter, and he clenched his fist, concentrating. A perfect mirror image of her Noble Phantasm, cast in ice and drawn from dozens of glowing magic circles, appeared behind him.

The Erza he knew loved the world. She would never give up on it.

This wasn't Erza.

"You ain't her anymore," he growled, planting his feet firmly to stand his ground and face her.


	3. Rule Breaker

**Notes for the Chapter:**

> Based on that awful scene in the Unlimited Blade Works route where Caster uses Rule Breaker—a cursed dagger that allows her to steal another Master's command seals and by proxy their Servant—on Saber, forcing her to fight her friends and allies.

The ruins were dark. Too dark. It made him nervous.

"Damn… where the hell is Natsu?" Gray grumbled, peering off into the gloom of a dim hallway.

His Servant thrust an armored hand into his chest to halt his forward progress. "Master, be careful!" she warned.

Gray looked down at the gaping maw of blackness just shy of his feet, bringing himself to a quick stop. He inhaled slowly through his teeth at the close call.

"Thanks, Erza," he said, shooting a smile at his red-haired companion.

She returned the gesture, then shot a glance down each of the branching hallways to the side. "This way," she beckoned him, spotting the faint flashes of firelight from Berserker splashing on the far wall.

Gray ran after her as she darted down that hallway, her armor clinking in a steady rhythm. Left, right, then left again they turned, coming up upon what looked to be a wide chamber.

 _Dammit Natsu, when will you learn to follow orders?_ Gray complained to himself, wondering how Lucy was faring against the minor familiars without her Servant.

They pulled up short as a rush of heat blew past their faces. Unshielding his eyes, Gray saw the pitched battle between the fire-wielding Berserker and the dark-haired Caster. Minerva was using her space-manipulation powers to dodge each and every one of Natsu's fireballs, standing calmly in place as her image appeared and disappeared around the room.

"Ice Make: Lance!" Gray shouted, bringing his hands up to form the streaking ice projectiles.

Caught off-guard by the side attack, Minerva failed to move out of the way in time. Several freezing darts splayed into her side, throwing her across the chamber.

"Berserker!" Erza called, brandishing her sword as she charged into the room and took up position. "Fall back!" she ordered. "Seek out her Master; he cannot be far!"

"Aw, I can take her!" Natsu insisted. His flaming fists clenched stubbornly. Minerva was up now and Natsu leapt past Erza to rush her. "Fire Dragon's Brilliant Flame!" he shouted, his hands spewing forth fire in a massive burst.

Minvera merely used her powers to side step the attack, teleporting in close to unleash a magical blast of her own.

"Ice Make: Shield!" Stepping in front of the intended target, Gray put up a solid frozen barrier, that absorbed the brunt of the blast, sparing Natsu from being deep fried.

Erza used the opening to attack herself, swinging her mighty sword in a series of rapid strikes that Gray could barely follow.

It forced Minerva to back off towards the other side of the room.

"Three on one is hardly fair," she chided, wagging her finger in a 'tut-tut' gesture. Reaching into her belt she pulled out a gleaming, jagged-bladed knife. An evil blade it looked, dripping with malice. Minerva grinned eagerly. "Let's even the odds!" she crowed.

"Ha!" Natsu scoffed, turning up his nose at the small blade. He turned to Gray and Erza in disbelief, thumbing at the Caster. "She seriously thinks that dinky little knife is—"

 _"Natsu, put your guard back up you idiot!"_ Gray shouted, but too late, Minerva had manipulated the space in the room to place herself behind the ice-mage and his shield, between him and Berserker.

The jagged knife was raised high. Natsu's eyes were only beginning to widen in shock.

"Natsu!" rang out a shrill female voice from another entrance. Lucy stood in the doorway, hand raised high and screaming desperately, "To me!"

The miracle of the Command Seal took hold, moving Natsu faster than humanly possible, dragging him back in less than a blink to Lucy's side, out of Minerva's reach.

The dagger sliced air. Minerva whirled around, not wasting momentum, changing targets in an instant. The twisted gleaming blade now streaked for Gray's chest.

He knew he couldn't block in time, already dropping hold of his shield to try and at least raise his hands.

Gauntleted hands hit his shoulder, pushing him forcefully, with magically-enhanced strength. Gray gasped as he was rammed aside, hitting the floor hard on his left arm and raising his head just in time to see the cruel dagger burying its tip into Erza's breastplate, piercing through, as Erza took the strike meant for him.

The swordswoman was frozen in shock, looking down in horror at the blade buried in her sternum. There was no pain. No blood. What—

All of a sudden there _was_ pain, a tremendous amount of it. Dark tendrils burst forth from her wound, lashing out around them, Minerva's sadistic smile gleaming white in the maelstrom. Erza shrieked, stiffening, her limbs twitching in place as electricity seemed to flood through her.

Gray reached out for her in panic. "Erz—aaah!" He suddenly doubled over as a burning sensation assaulted his hand, wrapping around the palm with his Command Seals. There was a tearing sensation. Something was ripped away from him; it almost felt like one of his limbs.

The burning stopped. Gray looked down at his hand, still intact, but missing the magic seals that marked him as a Master.

The seals that Minerva now proudly displayed on her own arm.

"Rise, my puppet!" she commanded with smug satisfaction.

Erza had been kneeling limp, her sword fallen by her side. Now, she reached for its hilt, slowly, awkwardly, as if fighting the movement. Her fingers closed on it and she staggered upright. Robotically. The motion not her own.

As his Servant, his friend, took up a place by Minerva's side, Gray realized what had happened. Somehow, Minerva had cheated. Broken the rules to make herself a Master. Stolen Erza from him.

And he saw red.

With a ferocious roar that would have made Natsu proud, Gray sprang up from the floor and charged Minerva.

"Give her back!" he screeched. "Give her back you witch! Erza ain't your slave!"

Minerva flicked him back with a sweep of her arm. Gray blew across the room, flung by the Caster's enhanced strength. Natsu and Lucy rushed to his side, grabbing up his arms to help him to his feet.

"Kill them all," Minerva ordered.

Erza's face strained. Her eyes met Gray's across the way, pleading, as she slowly raised her blade. "Gray…" she begged, her voice shaking with effort, as if her very voice was being constrained by the Command Seals on Minerva's hand. "Please… go…"

Gray shook his head, standing upright, Natsu and Lucy flanking him on either side and tensing for battle.

Like hell he was gonna leave her now.

"Not without you," he told her, icicles beginning to move up his arms.


	4. Clash of Ideals

**Notes for the Chapter:**

> A take on the Archer vs. Shirou fight in Unlimited Blade Works. Enjoy!

Ice clashed with ice.

The stuff was everywhere, flying through the air, coating the walls and floor, splintering into little glass fragments. Were she not determined to see this battle play out to its end, she might have left for a warmer room, or at the very least requipped into a more insulating suit of armor. As it was, Erza could not bear to tear her eyes away even for a second, fascinated and horrified and worried and awestruck all at once.

The older mirror image of Gray was haggard-looking. His face, still handsome, was nonetheless lined with tired wrinkles. The shockingly white mop of hair on his head was frayed with age, and unkempt. But he kept up with the younger Gray surprisingly well.

Her Master was determined to win, though. He had sworn to her he would. He'd promised her he would prove his other self wrong. The world _was_ worth saving. And he _would_ continue fighting for it until the very end. Even if everyone turned on him. Even if he fought alone.

Erza didn't want to believe in the future the older Gray had come from either. The ice mage that had been so kind to her, that had fought by her side to secure the Grail, that would never let her think her own life and place in history had been worthless… she couldn't bear to think that he'd end up so cynical and broken, resigned to culling the weak and unworthy from a twisted, heartless Fairy Tail.

It seemed even the future Gray hated the thought, else he would not be trying to kill his younger self, prevent his own existence, to spare himself the grief and the pain.

He was… exactly like her, Erza realized with startling clarity. She too had wished not to have been, to have her story erased. Out of guilt, out of shame, out of miserable self-pity and loathing.

She had been wrong to wish for that. Gray— _her_ Gray—had shown her that.

And so he must show himself.

Gray was knocked back and slid in place on his feet, one hand grabbing at the floor to slow his momentum.

Erza felt a flame in her heart and called out to him with renewed vigor. "Master! You can do it! You _must_ beat him!"

He paid her a grinning glance as he wiped a dribble of blood from his mouth. "Ain't lost a duel yet. I'll be damned if I lose one to myself," he assured her, eyes feverish with the thrill of battle.

Erza watched with pride as he called forth a slew of Ice Make projections, launching them towards his opponent as he charged forward.

Ideals clashed, ice shattered, and the battle continued on.


	5. Indomitable

**Notes for the Chapter:**

> Based on Shirou and Saber's face-off against Gilgamesh after their date in Fate route.

Stars glimmered out from the darkening sky, twinkling into being one by one. The evening breeze had a pleasant chill, wafting around them, lifting her crimson hair gently.

Erza pushed the wayward strands out of her eyes, inhaling slowly, savoring the cool night air. Wind whispered through the trees of Southgate Park and silver moonlight was gleaming on the leaves and branches. The fresh air was heavy with the scent of rich, damp earth, and just the faintest hint of Gray's aftershave.

The Saber-class Servant glanced aside at him and smiled.

"Gray…"

He startled a little at the sound of her voice, or perhaps her addressing him by name instead of calling him "Master". His dark eyes met hers.

Erza dipped her head. "Thank you," she said quietly. "Today was… pleasant." She shook her head wonderingly. "I did not know there would be so much to do in Magnolia but… you proved me wrong."

He relaxed at that, a warm smile spreading over his own face. "I'm glad," he said. "That you had fun."

They fell into companionable silence for a while, looking out across the park, their hands intertwined between them.

_"A date?"_ she had repeated skeptically that morning, when Gray had first proposed the day's plans to her.

_"Yeah. We both deserve a day off from the Grail War,"_ he'd argued. _"So come on, let's go into town."_

She had argued against it of course, citing the enemies still at large and the danger being out in public would bring.

But now, with Gray's warm fingers between hers, the calm of evening seeping into her, the rustle of wind in the trees and the distant warble of songbirds drifting to her ears… she felt more at ease than she thought she'd ever been in her life.

A niggling thought at the back of her mind said they should be getting inside soon, but Erza stayed it, wanting to linger here in this moment of blissful peace.

She gave a sigh of contentment, her heart warm.

She started to lean into Gray's shoulder.

"Well," a voice interjected. "Isn't _this_ a pretty scene?"

A chunk of pure ice dropped into Erza's heart, turning her stomach and her insides cold with dread. Her eyes widened in recognition of the voice and she found herself paralyzed, her limbs wound tight, unable to move.

_No… it couldn't be…_

Gray had stiffened beside her, twisting his head around to look and see. Ezra turned slowly as well, her mouth going dry and her breaths shaking shallowly.

A hooded figure stood casually down a ways from them on the park path, hands in its pockets, face shadowed. He came forward a few steps into the moonlight, the silver beams illuminating a handsome face with ragged blue bangs and a prominent tattoo across one eye.

"Have you forgotten me already, Titania?" a young, charming, horribly familiar voice came from him.

Erza trembled, fear knocking around inside her.

"J… Jellal…" she whispered.

He shook his head, an eerie smile playing at his lips. "That's not my name anymore, Titania," he scolded gently. "You know that."

Erza swallowed the thick terror that was threatening to strangle her. So, now they knew the identity of the mysterious Archer-class Servant. The knowledge was little comfort to her. Her body trembled. Her mind screamed in denial.

She couldn't… she couldn't face him again. Not again…

_**Please**_ _not again_ , she begged whatever gods or higher beings were listening.

-FT-

Gray felt her hand shaking inside his and gripped it tighter, protectively, shooting the newcomer a glare.

"If you're gonna fight us, just go on and do it," he challenged. "You won't win the Grail."

The stranger tilted his head. "Fight?" he repeated. "Oh no, I don't intend to _fight_ you. It would be very troublesome to keep Erza here if I injured you too badly."

Gray gnashed his teeth. "Then what do you _want,_ you weirdo?" he demanded.

The man extended a hand out, palm up, towards Erza. "All I want is my beloved Titania," he said. His eyes were lined with affection and something dangerous hiding in the depths. "Erza…" he called gently.

She inhaled sharply through her teeth next to him, tensing.

"Come with me and no one else has to get hurt."

There was a vague threat underlining the words, and Gray let go of Erza's hand, placing himself in front of her, arms outstretched and shielding.

"You can't have her," he growled.

"Gray…" Erza's voice was thin and strained, and she shook her head in small, tight motions. "Please… He'll kill you."

"I don't care," Gray snapped back. "I won't let you go with him."

The man dropped his hand, drawing himself up with anger. "Do you even know who I am, boy?" came his question, tone chilling.

Gray's hands tightened into fists. "You're the jerk who made Erza cry," he said.

The stranger stretched to his full height, tossing back his hood, letting the moonlight shine down starkly across his bright blue hair.

"I am Siegrain!" he declared, throwing his arms out. "Champion of Caelum! Builder of the Tower of Heaven that will pierce the veil between life and death!"

"Bastard," Gray spat, unimpressed. "You broke her heart. Made her not want to _exist_!"

He felt Erza gathering herself together beside him and looked over just in time to see her requip into her battle armor. She lifted her sword, brandishing it.

"Go, Master," she told him, her eyes steely and determined. "I will keep him at bay. Go to the guild hall and get the others."

Gray shook his head, already stripping off his shirt. "No," he said firmly. "We'll face him together."

"You don't stand a chance against him," she said quietly, the grip she had on her sword shaking.

"I ain't letting you fight him alone," he argued hotly, squaring off with her. His voice and expression turned softer. "Because you and I… we're Fairy Tail. We're a team."

His clenched fists loosened and his hands hung limp by his sides. His eyes were earnest, agonized, pinching under the weight of his words.

"Because I _love_ you," he strained out.

Something changed in Erza's expression. A fire lit behind her eyes, a wild look that shone with passion and warmth and brave determination.

Her shaking stopped. She stood firm and unmovable. Gray's words had stripped away her fear and now she shone with strength and courage, almost glowing in the moonlight, a flaming Heroic Spirit.

"You're an idiot," she said, laughter under her words. "But don't ever change."

She shifted to face their opponent, stepping closer to his side.

"Together it shall be," she determined, raising her sword again.

Gray stood next to her, readying himself for battle, ice beginning to curl up his arms. They faced off against the ghost from Erza's past, indomitable and ready for whatever he threw at them.

They would not break They would not yield.

They were Fairy Tail.

And they were going to win.


End file.
